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Poster at ICDE conference in Vienna

held 23rd June 1998 room 6 at 4 p.m. (16:00)
you can get more details on ICDE conference here
full programm is here

a. ID-No: ICDE - 99 - POSTER - ID Nr. t2b02913
b. Author: Dipl. Ing. Dusan Statelov, MAINDATA, s.r.o., Slovakia

Author's bibliography:

Dusan Statelov 36, graduated in 1985, is working with data broadcasting technologies since 1992. In 1993 he has established a Finsat, s.r.o. a joint-venture with a Slovak-American Enterprise Fund. Finsat was first real-time satellite based financial information system providing information from emerging capital markets and news agencies in Central Europe fully developed in Slovakia. In 1996 he established MAINDATA, s.r.o., which focuses on data broadcasting via analogue and digital television. His idea of interactive broadcast system gave a basis of Hybrid-Net system, which has been installed in February 1999 for the World Bank in Washington, D.C.

Data broadcasting via DIGITAL TELEVISION with return path via INTERNET is emerging technology ideal for OPEN/DISTANCE TELE-EDUCATION systems.

Combination of Internet and Digital Television represents today a combination of two most broadly available communication networks. Internet and Digital Television complements each other substantially, when the Internet gives to Digital Television interaction, and Digital Television gives Internet High speed Infrastructure to the end user (Mbit/s) and native multicast capabilities ideal for video and audio broadcasting.

Today it is practically and economically impossible to operate high quality Video-based Tele-Education via Internet as it requires much more capacity as it is normally available on the Internet. When a normal Internet user access speed is 22 kbps, video requires communication speeds at around 1 Mbps (what is 50 x more). Such capacity is problem for often for ISPs backbone itself and almost always for user access speed.

By implementing HYBRID-NET communication architecture fundamentally changes when high speed stream of video data (1 Mbps) coming from the lector is "flying" to the students via Digital TV (satellite or terrestrial). That solves all mentioned communication problems for all students:

How does the Interactive Broadcast based Tele-Education system works ?

Lector provides the trainee from the central studio, where from the video and audio is transmitted to the satellite up-link station. This station up-links signal to the satellite at the orbit (located 36 km above the equator) and then signal is distributed (down/link) to unlimited number of students or employees, received by TV antennae and displayed either on the TV or PC screen.
During the lesson, participants may react on the speech interactively and ask questions by typing them on the computer or simply speaking into microphone. These questions are delivered to the centre via Internet back to the lector.
The question is then displayed on the screen in the Main broadcast channel followed with the explanation of the lector. It creates good platform for exchanging information where other participants benefit from the questions of another one.
There is a high asymmetry in intensity of communication in particular direction (in and out) typicall for Tele Education systems. Thanks to Internet return path added to Digital TV Tele-Seminars held via Hybrid-Net system are interactive in opposite to one-way only Digital TV broadcast with passive reception.

Depending on the return path implement into the system various functionality can be reached:

• Dial-up via Internet (low speed) > chat, phone over IP
• ISDN, dedicated line > video conferencing

The seminars can be provided either alive or can be pre-recorded.

Advantages of the Tele-Education system are:

• Low communication costs with high video quality
. ...(thanks to native multicasting)
• Wide geographical availability of ODLS (as satellite footprint):
• Interactivity
• Inexpensive satellite receivers (300 USD)
• Increased flexibility
• Savings of

Travel costs
Accommodation costs
Labour costs
Time (no need to travell)

The system can be effectively used for:

Virtual Universities
Vocational and continuing training
For large organisations like government, banks etc.
This system was installed for the African Virtual University - the project of the World Bank in Washington, D.C.